/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package unc.pds.servlets;

import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.URLEncoder;
import javax.ejb.CreateException;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import unc.pds.data.Consts;
import unc.pds.filemodel.FileRemote;
import unc.pds.service.ServiceBeanRemote;
import unc.pds.service.ServiceBeanRemoteHome;

/**
 *
 * @author Mikhail
 */
public class DownloadServlet extends HttpServlet {

    public static final int BUFSIZE=2048;
   
    /** 
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("application/octet-stream");
        request.setCharacterEncoding("UTF-8");
        OutputStream out = response.getOutputStream();
        try {
            String id = request.getParameter("id").toString().split("/")[0];
            ServiceBeanRemote service = ((ServiceBeanRemoteHome)(new InitialContext()).lookup("ejb/ServiceBean")).create((Long)request.getSession().getAttribute("sid"));
            FileRemote file = (FileRemote)service.getByKey(new Long(Long.parseLong(id)));
            String fileName = "files\\"+file.getKey();
            File f = new File(fileName);
            int length = 0;
            ServletContext context = getServletConfig().getServletContext();
            String mimetype = context.getMimeType(fileName);
            response.setContentType((mimetype != null) ? mimetype : "application/octet-stream");
            response.setContentLength((int) f.length());
            String userAgent = request.getHeader("USER-AGENT").toLowerCase();
            if (Consts.DEBUG_MODE) System.out.println("userAgent = " + userAgent);
            String realName = URLEncoder.encode(file.getName(), "UTF8");
            if (userAgent != null
                    && (userAgent.contains("chrome")
                    || userAgent.contains("msie")) ) {
                response.setHeader(
                        "Content-Disposition",
                        "attachment; filename=\"" + realName + "\"");
            } else {
                response.setHeader(
                        "Content-Disposition",
                        "attachment; filename*=\"utf-8'" + realName + "\"");
            }
            byte[] bbuf = new byte[BUFSIZE];
            DataInputStream in = new DataInputStream(new FileInputStream(f));
            while ((in != null) && ((length = in.read(bbuf)) != -1)) {
                out.write(bbuf, 0, length);
            }
            in.close();
        } catch (Exception e) {
            
        } finally {
            out.flush();
            out.close();
        }
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    } 

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>

}
